Apple has released AirPort Extreme Base Station Firmware 5.0.4. The update is recommended for all customers with French AirPort Extreme Base Stations or if your AirPort Extreme Base Station stops responding after being on a busy Ethernet Network. It also fixes an issue where an AirPort Extreme network appears to be unavailable as displayed by the AirPort Menu Extra or the Internet Connection application. The new firmware revision is not for use with the original (Graphite) or the dual-Ethernet (Snow) base stations.
